US 3001225 A
Description (OCR text may contain errors)
Se t. 26, 1961 H. D. SQUIRE DUAL PIVOT FREEZER HINGE Filed Jan. 10, 1958 United States Patent 3,001,225 DUAL PIVOT FREEZER HINGE Herbert D. Squire, Galesburg, Ill.', assignor to Admiral Corporation, Chicago, Ill.,v a corporatiou of Delaware Filed Jan. 10, 1958, Ser. No. 708,089.
4 Claims. ((116-1 66) This invention relates to improvements in hinges for refrigerators and more particularly to a counterbalance hinge for a chest type refrigerator. p
In the construction of chest .t'ype refrigerators it is common to provide a cabinet having an open top which is closed by a lid that is usually hingedly' connected to the cabinet along one edge which is usually the back edge; These lids are usually relatively heavy, because they are large and insulated, and it is desirable to prothem to be opened more readily, to hold them in the open position and. to reduce the weight on the sealing gasket when the lid is closed and to still enable them to be maintained in closed position withoutthe use of a Patented Sept. 26, 1961 In the drawings the hinge structure is illustrated in its most simple form. As' viewed therein there is shown a conventional cabinet .10 having a back wall 11. The cabinet is provided with the usual top opening the edge of which is provided with a breaker strip 12. A lid is also provided and carries a sealing gasket 16 which is arranged to contact the breaker strip 12 to provide a seal. The gasket. may be any of the usual compression or distortable members well known in the art.
Rearwardly of the cabinet there is provided a hinge U element which includes a bracket part 20 having flanges 21 which enable it to be secured to the back wall by screws 22. Upwardly of the brackets 20 is a hinge leaf or guide carrying member 24 which extends above the top edge of the cabinet rearwardly of the rear edge of the lid. It should be pointed out that the bracket 20 may vide for means to counterbalance the lids to enable latch. The more. common means for providing the counterbalancing elfect is by the inclusion of springs in the hinge structure. I
Although various types of spring balanced hinge structures have been proposed, certain deficiencies have been apparent, since, in the simpler types, the spring, if sufficient to overcome the Weight of the lid also caused an accelerated operation ofthe lid during opening resulting in a tendency to overtravel when the lid reached the open position. This caused an undue strain and sometimes failure of the hinge. Usually the opening of the lid is slightly less than 90 from the horizontal closed position. Although various mechanisms have been proposed to overcome the above difiiculties they have been very complicated and expensive to make, difiicult to install and service and frequently were very noisy in operation.
By the present invention I have provided a counter balance hinge structure which is very simple and inexpensive to manufacture, is quiet in operation and simple to install. Furthermore, it requires a minimum of service and is elfective to prevent the wide open overtravel previously mentioned. The construction is such that the desired amount of weight (which may be 15 lbs.) is present to hold the door closed but that weight is rapidly overcome shortly after the door has been raised slightly by a rapid change in the counterbalancing forces.
Still other advantages of the invention and the invention itself will become more apparent from the following description of an embodiment thereof which is illustrated by the accompanying drawings and form a part of this invention.
In the drawings:
FIG. 1 is a fragmentary view of a refrigerator cabinet and lid illustrating a simple form of the hinge of my in vention with the lid in the closed position;
FIG. 2 is a similar view showing the lid in the final stage of movement; and
FIG. 3 is a view showing the lid at the end of the second stage of movement.
Briefly, my invention contemplates a hinge structure wherein a first pivot point for the lid is provided and wherein the lever arm, represented by the point of connection of the spring to the lid hinge member and its spacing from the pivot point for the lid, rapidly increases as the lid is opened to a predetermined position, after which the lid pivot point is shifted and the lever arm made substantially constant to make the spring exert less force and to thus slow down the door opening as it reaches the full open position.
be considered'as a housing having spaced parallel side walls 20 and a back wall 20a, and that the side Walls 20 each have a flange 21 which may be either inturned or outturned'. Also, the bracket could be a single plate in some instances but spaced parallel plates provide a more desirable. construction.
The bracket is provided with pairs of guideways on each side. The lower or first guideways are positioned near the base of the member 24. Above this are upper or second guideways '32 positioned near the upper end of the member 24. Each of the guideways may be formed by striking an opening in the member 24 in such a manner as to provide laterally extending bearing flanges.
The positioning of the pairs of guideways may be varied but each pair bears a definite relation to the other. Each being arcuate, the arc being generated by a radius for each guidewa-y from the same end of the other guideway.
The lid is provided with a rearwardly extending bracket 40 having a pair of flanges 41 enabling it to be secured to the rear edge by screws 42. The bracket projects rearwardly of the lid and extends alongside the member 24. This may likewise be made with a pair of walls 40 in spaced parallel relation to each other and extending inside or outside of the walls 24. The walls carry between them, fixed pivot pins 44 and 45 which are slidably disposed in the guides 30 and 32 respectively.
As can best be seen in FIG. 1, when the lid is in the closed position, the pin 44 is in the outward end of the slot 30 and the pin 45 is in the inward end of the slot 32.
At the upper end of the bracket 40 there is provided a spring pin 50. This pin is disposed above the pins 44 and 45 and slightly outward of the pin 44 which in turn is outward of the pin 45.
The position of this pin may be varied and is largely determined by the amount of lid weight to be counterbalanced. A spring 52 is provided and has its lower end hooked to an adjustable screw eye 53 on the lower bracket and its upper end hooked on the pin 50. The adjustable screw eye enables the tension on the spring to be adjusted. It should be pointed out that the length and position of the slots 30-32 may be varied as well as the placement of the pins 44-45 to provide the desired action depending upon the size and weight of the lid.
In operation, it being assumed that the lid is in the closed position, the spring 52 has the tension adjusted until the desired amount of sealing weight (uncounterbalanced weight) is present to hold the lid closed. When the lid is raised the pivot action first takes place about the pin 44.
In the closed position, the elfective lever arm represented by the displaced position of the spring pin 50 and the point of securement for the screw eye 53, is close to the pivot 44. As the lid is raised the pin 50 moves to the left increasing the effective lever arm; the pin 45 moving in the slot 32. During all this time the lever arm has been rapidly increasing in eflective length. The above action continues until the pin 45 bottoms in the outer end of the slot 32.
At this time the pivot for the lid shifts from the pin 44 to the pin 45 and the pin 44 now moves in the slot 30. It will be noted that, with the shift of pivot points,
the effective lever arm now ceases to increase in length and becomes substantially constant. Since the tension on the spring is decreasing the counterbalance forces become less as the lid raises higher and when the extreme open position is reached, as shown in FIG. 3, the forces are merely sufiicient to hold the lid in the open position. Obviously the pins 44 and 45 also prevent further travel of the lid in an opening direction by pro viding positive stops when both pins 44 and 45 have reached their limit of travel within their respective guideways '30 and 32. This arrangement effectively preventing over travel of the lid beyond a desirable full open position.
When the. lid is closed, the reverse operation takes place.
It should be pointed out that the slots may be so proportioned and positioned that a decreasing effective lever arm may be realized if desired.
It will thus be apparent that I have provided a spring hinge which is noiseless in operation. That sufficient unbalanced weight is present with the door in the closed position to allow the door to remain closed without the use of a latch and that to a certain extent this weight may be controlled by adjusting the tension of the spring, but that the main balancing is effected during actual design by the distance of the spring pin to the left of the lower hinge pin and the change of lever arm is effected by the length and relative positions of the slots. It is also apparent that immediately upon starting to raise the lid the efiFective lever arm rapidly increases to reduce and quickly overcome the unbalanced weight and that as the lid reaches the open position the elfective forces overcoming the weight are reduced such that as the lid reaches the full open position it does so gently and without undue strain upon the hinge.
Having thus described my invention, I am awarethat numerous and extensive departures may be made therefrom without departing from the spirit of the invention as defined in the appended claims.
1. A hinge construction for a cabinet having aback Wall and a top. opening and a lid for closing the top opening comprising a first support secured to the back wall and formed with a pair of pivot pin guideways therein, a second support secured to the lid and having guideway is vertically spaced above the other guideway.
3. A device as described in claim 1, wherein the pins are movable in the guideways and in the extreme limits of movement are disposed in opposite ends of the respective guideways.
4. A device as described in claim 1, wherein the connection of the spring to the cabinet is fixed and the connection of the other end to the second member is spaced to one side of the pivot pins. 7
' References Cited in the file of this patent UNITED STATES PATENTS 2,334,951 Parke et al. Nov. 23, 1943 2,435,670 Buehler Feb. 10, 1948 2,584,372 Swedman Feb. 5, 1952 2,793,387 Odell May 28, 1957